N-Ratio Buffer

Buffer input data into integer-multiple-sized frames

Since R2026a

• 

Libraries:
DSP System Toolbox / Signal Management / Buffers

Description

The N-Ratio Buffer block buffers data into blocks of length equal to integer N multiples of the input frame length. The integer ratio N between the output frame length and input frame length is given by the Output-to-input frame length ratio parameter.

Here is an illustration that shows how the block buffers the data. By default, the buffer is initialized with zeros. As new data comes in, the block groups this data into lengths of the specified size. When sufficient data is not available, the block outputs zeros.

The N-Ratio Buffer block optimizes the memory used in the generated code for P- to NP-frame conversion.

Examples

Buffer Input into Frames Using N-Ratio Buffer

Use the N-Ratio Buffer block to buffer multichannel signals of frame length 1 into multichannel signals of frame length N, where N is a positive integer greater than 1.

This figure is a graphical representation of a signal with frame length 1 converted into a signal of frame length N by the N-Ratio Buffer block.

In this example, a two-channel 1-sample-per-frame signal is buffered into a two-channel 4-samples-per-frame signal using an N-Ratio Buffer block.

Open the ex_nratiobuffer_tut model. The Signal From Workspace block has these parameters set:

• Signal = [1:10;-1:-1:-10]'

• Sample time = 1

• Samples per frame = 1

• Form output after final data value = Setting to zero

Based on these parameters, the Signal from Workspace block outputs a signal with a frame length of 1 and a sample period of 1 second. Because you set the Samples per frame parameter to 1, the Signal From Workspace block outputs one two-channel sample at each sample time.

Save these parameters and close the dialog box by clicking OK.

Double-click the N-Ratio Buffer block and set Output-to-input frame length ratio to 4. The N-Ratio Buffer block outputs a signal with a frame length of 4.

Run the model.

This figure shows the model behavior during simulation.

Ports

Input

Input — Data input

scalar | vector | matrix

Specify the data input as a scalar, vector, or a matrix of size P-by-Q.

Data Types: single | double | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | Boolean | fixed point
Complex Number Support: Yes

Output

Output — Output of N-ratio buffer

scalar | vector | matrix

Output of the N-ratio buffer, returned as a scalar, vector, or a matrix of size NP-by-Q, where N is the value you specify in the Output-to-input frame length ratio parameter.

Data Types: single | double | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | Boolean | fixed point
Complex Number Support: Yes

Parameters

To edit block parameters interactively, use the Property Inspector. From the Simulink^® Toolstrip, on the Simulation tab, in the Prepare gallery, select Property Inspector.

Output-to-input frame length ratio — Ratio of output frame length to input frame length

64 (default) | positive integer

Specify the ratio of the output frame length to the input frame length, N, as a positive integer.

Block Characteristics

Data Types	Boolean | double | fixed point | integer | single
Direct Feedthrough	no
Multidimensional Signals	no
Variable-Size Signals	no
Zero-Crossing Detection	no

Extended Capabilities

C/C++ Code Generation

Generate C and C++ code using Simulink® Coder™.

The N-Ratio Buffer block optimizes the memory used in the generated code for P- to NP-frame conversion.

Version History

Introduced in R2026a